Abstract

Sounds in real world environments such as animal calls and human speech are complex and often occur in rapid succession. In light of this, it is important to gain an understanding of how the rate of acoustic stimulation influences the units’ basic response properties. Previous studies of frequency tuning were generally based on investigating neuronal responses to tonal stimuli presented in isolation, and the results derived therefrom were assumed to accurately portray the cell’s response range. However, the firing history of an auditory neuron has been shown to shape its response to subsequent sounds. The goal of the present study was to investigate the frequency tuning characteristics of neurons in the inferior colliculus (IC) of the little brown bat to tone pulses presented at various rates. Eighty‐five percent of the IC neurons studied showed rate‐dependent changes in their frequency selectivity. Half of these neurons exhibited narrowing of their frequency response range at higher rates. These results indicate that the response properties of central auditory neurons at low stimulation rates do not necessarily reflect the units’ response properties to sounds presented at high and behaviorally relevant rates. The possible cellular mechanisms and behavioral importance of this effect are discussed.